1. Field of the Invention
The present invention relates to a toner cartridge for supplying toner to an image forming apparatus.
2. Description of the Related Art
An image forming apparatus has a toner cartridge for supplying toner to the apparatus. The toner cartridge is inserted in the image forming apparatus in a removable manner. Also, the toner cartridge is configured such that the user can exchange the toner cartridge himself or herself when the toner cartridge is emptied of toner. In addition, a filling opening is provided in the toner cartridge and the toner is supplied through the filling opening. In the toner cartridge, a mixer is rotated constantly so as to prevent the toner from solidifying inside the toner cartridge.
In many cases, a manufacturer recommended product including a genuine product is set with respect to the toner cartridge such as above. This is because using a toner cartridge other than the recommended product is considered to cause a possible problem in the image forming apparatus. In a color image forming apparatus, the toner cartridge needs to be inserted in an appropriate position depending on a color of toner. For this reason, there is also an image forming apparatus which is configured so as to discriminate whether a inserted toner cartridge is recommended or not, and a type of the toner cartridge including a type of toner.
Jpn. Pat. Appln. Publication No. 2001-255728 discloses a slit disk which is provided at each toner cartridge and attached on an axis of a rotary shaft of a paddle, and in which slits are formed with specified intervals in a peripheral direction and slit intervals are mutually differently formed. A photosensor can detect the slit and detect a type of the toner cartridge from a detected signal.
U.S. Pat. No. 6,542,709 discloses a method of driving a paddle wherein a driving gear is arranged on one end of an auger for conveying toner, and a driven gear provided on one end of the paddle is rotated by the driving gear through an indirect gear.
In addition, Jpn. Pat. Appln. Publication No. 2004-264460 discloses a cartridge which has a paddle and an auger rotated by a driving gear, a driven gear, etc. provided on an external side of a toner cartridge.
However, when a slit is detected by rotating an axis of a paddle in which slits are formed as disclosed in Jpn. Pat. Appln. Publication No. 2001-255728, and when a rotary force of the paddle is a driven rotary force based on a rotation of an auger such as the one shown in U.S. Pat. No. 6,542,709, there is need to take into consideration a necessary rotation to ensure correct detection of the slit. However, a toner cartridge taking into consideration the above point does not exist, and this has resulted in detection in error.
When the inventors of the present invention attempted to have a toner cartridge having a gear on an external side of the cartridge optically detect the slit disclosed in Jpn. Pat. Appln. Publication No. 2001-255728, there occurred a problem that the gear entangles a variety of lead wires used for detection.
The present invention is invented in view of the above circumstances. An object of the present invention is to provide a toner cartridge which can correctly discriminate a type of the toner cartridge inserted in the image forming apparatus and a toner cartridge which does not interfere with optical detection carried out by the image forming apparatus.